% Copyright 2020 Makani Technologies LLC
%
% Licensed under the Apache License, Version 2.0 (the "License");
% you may not use this file except in compliance with the License.
% You may obtain a copy of the License at
%
%      http://www.apache.org/licenses/LICENSE-2.0
%
% Unless required by applicable law or agreed to in writing, software
% distributed under the License is distributed on an "AS IS" BASIS,
% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
% See the License for the specific language governing permissions and
% limitations under the License.

function [p] = select_index(p, mask, select)
other = p.select(~ismember(p.select, mask));
offset = sort(mask);
offset = offset(1) - 1;
selection = mask(ismember(mask, offset + select));
p.select = sort([other, selection]);
p.nselect = 1:p.count;
p.nselect(p.select) = [];
p.map = zeros(p.count, 1);
p.map(p.select) = 1:length(p.select);
